docs: def get_operator_index(self, name):
          """|coro|
  
          Gets the operators index from the operator definitions dict
  
          Returns
          -------
          str
              the operator index"""
          opdefs = yield from self.get_operator_definitions()
  
          name = name.lower()
          if name not in opdefs:
              return None
  
          return opdefs[name]["index"]